Fiberoptic Interferometer For Relative Phase Detection

The recent developments in the field of high-power semiconductor lasers open a broad area of applications, medical, measurement developments, pumping of solidstate lasers and furthermore. For almost all of these applications it is necessary to collimate and handle the laser beam power by optical elements. On the other side high power laser diodes are mostly gain-guided multi-stripe-arrays exhibiting wavefront aberrations which are a function of drive current, temperature, optical window in the package and even might differ from sample to sample. In order to correct for these aberrations and get an optimized optical system not only the beam intensity distribution has to be known, but also the relative phase of the wavefront in comparison to an ideal spherical wave. A fiberoptic interferometer is described which measures the relative phase of the radiation field locally with high resolution. Summing up the data and assuming a rectangular symmetry the complete wavefront can be reconstructed.© (1989) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.